Part A: Four healthy subjects will each receive one injection of 123-I INER. Serial whole body planar imaging in the anterior and posterior projection will be performed over the 8-9 hour period following injection of 5 mCi of 123-I INER and again at 18-24 hours following injection. Venous blood data will be acquired at each imaging time point. In addition a 24 hour urine collection will commence following radiotracer injection. Whole body and source organs uptake will be analyzed on anterior and posterior images for calculating the radiation absorbed doses to organs. Plasma and urine metabolites will be characterized and safety assessments obtained. Serial safety assessments will include vital signs, serum chemistries, CBC, urinalysis, and EKGs.